Adhesive lubricants



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Uni es; Sees Pam o ADHESIVE LUBRICANTS George R. Cook, Arlington Heights, and Warren-2V. Cortiss, Crystal Lake, 111., assignors to The Pure Oil Compauy, Chicago, 111., a corporation of Ohio No Drawing. Application July 23, 1957 Serial No. 673,557

11 Claims. (Cl. 252-57) This invention relates to new and useful improvements in lubricant compositions and more particularly to a lubricant composition characterized by its adhesiveness to metal surfaces.

One of the most important characteristics of certain lubricants, such, as those used on wire rope, open gears, etc., is their ability to remain on the eXposed members of such assemblies. That is, the lubricant must possess sufficient tackines's to adhere to the members, and yet be sufliciently fluid to permit unrestricted operation of of the moving members. In the case of wire ropes, the lubricant must adhere to the surfaces thereof Without making them inflexible or otherwise impeding their use. In addition to being adhesive toward metal, the lubricant must also be cohesive. That is, it must stick to itself, as well, as to the. machine component or rope, so that a coating of adequate thickness can be maintained Therefore, in the formulation of good lubricants of thisftype,

an adequate adhesion-cohesion balance must 'be "maintained. While this balance may be obtained in part by blending certain high viscosity petroleum fractions, including asphalt, such blends fall far short of the level required for adequate tenacity, and various addends have been used in the past to enhance the adhesiveness of the lubricant. For example, so-called waX-tailings have been used (US. Patent 2,716,085). However, these materials have generally been petroleum-derived by-products of varying availability, and, being by-products, have been 2,910,440 Patented Oct. 27, 1959 which derives its'adhesive characteristics from an addend which is uniform in composition, readily available and inexpensive.

Another object of this invention is to provide a new and improved adhesive fiuidpetroleum lubricant which .is more adherent for the amount of adhesive addend to increase the viscosity thereof and polymerized methyl esters of rosin in an amount suflicient to provide the desired adhesive qualities.

Other objects and features of this invention will become apparent from time to time throughout the specification and claims as hereinafter related.

This invention is based upon the discovery that a superior, readily reproducible, tacky but fluid, lubricant can be prepared by incorporating 1 to 15% by weight of polymerized methyl estersof rosin in viscous residual oils obtained from the'produ'cti'on of lubricating oils. The viscous oils which are used as the base for these adhesive lubricants may be the residues from the distillation of lubricating oils, or preferably the solvent-extracts from the solvent-refining of lubricating oils. These oils may be used alone or blended with other oils orwith asphalt to produce base oils of the desired viscosity, which may then be, provided with the desired adhesiveness by addition of the polymeriz 'ed methyl esters of rosin.

In preparing adhesive fluid lubricants of this type the various components are merely placed together in any conventional mixing apparatus that is capable of thor-' sive lubricants. These lubricants were prepared to correspond to commercial adhesive lubricants having average viscosities at 210 F. (SUS) of 500, 1000 2000, 3Q00 and 5000, respectively. The composition of these lubricants and their physical properties are set forth in Table I. The lubricants were compounded as abovedescribed by simple mixing at 300"-325 F.

the adhesive characteristics of lubricant films.

3 Table 1 [Composition by weight percent] A B C D E Component:

Polymerized methyl estor of rosin 1 12.0 12.0 12.0 12.0 12. 0 Neutral solvent-extract 6. Bright stock extract 81. 5 75. 0 57. 0 49.0 40. 0 Asphalt 4 13.0 31.0 39.0 48. 0 Physical properties:

Gravity API) 2 9 9 8.9 8 5 1 9 Flash F. 480 550 535 540 540 Fire F.) i 575 623 630 620 025 Viscosit at 21 (SUS)? 501 1, 016 1, 974 2, 991 5, 144 Pour point F.) +60 +85 +90 +95 1 Polymerized methyl esters of rosin used in this composition are cominercially obtained from Hercules Powder 00. under the designation P.A.D. or "Polymerized Abalyn, Dark. These polymer zed methyl esters rosin are obtained as the residue from the vacuum distillation of dark methyl ester of rosin. Polymerized methyl esters of rosin used in this composition have the following properties:

Molecular weight 760 Melting point, I 1; 212 Acid numben 4 2 Neutral oil extract used in this composition was the phenol extract from the solvent-refining of 80/100 neutral oil, and has the following proper'ties: 165. 5 41.0 0.9509 32% Fire, F Color (ASTM-NPA) 3%+ (dil.) Pour point, F 35 Carbon residue (weight percent) 0. Sulfur weight percent).-- 2. 01 Steam emulsion number 3132 3 Bright stock extract used th composition was a solvent-extract from the solvent-refining 0f-150/100 bright stock and had the following roperties:

p Viscosity at 100 F. (SUS) 27,000

Viscosity at 210 F. (SUS) 369. 2

Sp. gr. (60/60 F.) -II 0. 9725 Flash, F. 555 Fire, 530 Color (ASIM-NPA) Pour point, F 4 5i Carbon residue (weight perccn 26 Sulfur weight percent) 2.35 Steam mulsion numben. 1200+ Acid number (elect) 2. 95

4 Asphalt used in this composition had the following properties:

Softening point, R. dz B. F.) 197 Sp. gr. (77/77 F.) 1.026 Ductility 2/2 Penetration at 32 F 20 Penetration at 77 I 31 Penetration at 115 F. N. 61 Carbon tetrachloride solubles (weight percent). 09. 8 Ash as oxide (weight percent) 0.23

Compositions A, B, C, D, E, produced as described above, each and all have been found to have superior properties as adhesive fiuid lubricants, and may be used for wire lubricants and for lubricating exposed gears. Compositions A, B and C were each tested ona special test apparatus (which is described and shown more completely in co-pending application, Serial No. 582,561,

filed May 3, 1957), which has been devised to determine In this apparatus a small steel test plug is positioned on a predetermined spot on an electromagnet by use of a jig. The plug is then lowered to within 0.0005 of a film of test lubricant that has been prepared to a thickness of 0.005". The electrical current to the electromagnet is then adjusted to exactly 10 milliamperes, and turned off, allowing the plug to rest on thefilm of test lubricant.

Simultaneously with the opening of the switch, the start Tac tension value. This test provides a very accurate measurement of the adhesive characteristics of a lubricant film. Since the adhesive characteristics of lubricant films vary considerably with viscosity as well as adhesive additives, it is desirable to compare not only the adhesive characteristics as measured by the Tao tension value but also the relationship of the Tao tension value to the viscosity of the lubricant. This ratio, i.e. the Tao tension value divided by the viscosity at 210 F. in SUS, is referred to as the Tao tension factor and is a convenient unit for comparing the adhesive characteristics of lubricants which vary widely in viscosity.

Lubricant compositions A, B, and C of the above series of adhesive lubricant compositions were tested to determine their magnetic Tac tension values and Tac tension factors. Composition A was found to have a Tac tension value of 60.2 and a Tac tension factor of 0.121. Composition B had a Tac tension value of 138 and a Tac tension factor of 0.135;. Composition C had a Tac tension value of 293 and Tac tension factor of 0.148. Compositions D and E were too viscous to be tested by this method but have been found satisfactory in actual use as Wire lubricants. These lubricant compositions were compared with commercial adhesive petroleum lubricants, prepared according to U.S. Patent 2,716,085, in the same viscosity ranges and were found in each case'to have Tac tension values and Tao tension factors from 30 to 50% greater than the corresponding commercial lubricants.

Additional experiments have shown that the normal variations in the various ingredients used in this improved lubricant composition will result in a variation of 13- 1% in viscosity from the average values indicated. Thus composition A may vary in viscosity from 485 to 515 SUS at 210 F. Composition B may vary from 975 to 1025, composition C from 1925 to 2075, composition D from 2900 to 3100, and composition E from 4850 to 5150 (SUS at 210 F.). Experimental data have shown that satisfactory lubricants can be made using residual oils from the preparation of lubricating oils, e.g., tube still bottoms, as in U.S. Patent 2,716,085, or a blend of solvent-extracts as in compositions A to E of this specification. These residual oils may be increased in viscosity by addition .of asphalt and provided with the necessary adhesiveness by addition of polymerized methyl esters. of rosin. The polymerized methyl esters of rosin may be used in the range from 1 to 15%, although therange of 12 to 15% is preferred. At concentrations above 15% the increase in adhesive properties is disproportionate to the added cost of the additive. At concentrations below 12% the adhesive characteristics are satisfactory but decrease in proportion to the concentration of the additive. Thus, the lower concentrations of additives may be used for less viscous oils where less adhesion is required. H In the formulation of less viscous adhesive oil compositions (in the general range of composition A) compositions including: 7585% by weight of solvent-extract from solvent-refining of vis. bright stock, 5 to 10% by weight of solvent-extract from solvent-refining of neutral oils, and 12-15% by weight of dark polymerized methyl esters of rosin, are satisfactory for adhesive-lubricants for the purposes indicated. The more viscous grades of adhesive lubricant compositions are prepared by blending 3580% by Weight of solvent-extract from solvent-refining of 150 vis. bright stock, 10 to 50% by-weight asphalt, and 12-15% by weight polymeriz'edrnethyl esters of rosin. As it is apparent from the foregoing description, the exact ranges of percentages of the oil base, asphalt, and polymerized methyl esters of rosin are not well defined sinc e these proportions may be varied to produce lubricants of varying viscosity and adhesiveness, depending upon the type of adhesive lubricant needed and the cost of preparing the same.

While there have been described herein several preferred embodiments of this invention, and several specific examples of the best modes of carrying out this invention, it should be understood that within the scope of the appended claims this invention may be practiced otherwise than as specifically described.

=What is claimed is:

1. A petroleum lubricating composition characterized by its adhesiveness to metal surfaces, comprising a major proportion of a viscous residual oil of the class consisting of residues from the distillation of lubricating oils and solvent extracts obtained in the solvent refining of lubrieating oils and 1-15% by weight of the dark polymerized methyl esters of rosin obtained as the residue from the vacuum distillation of the dark methyl ester of rosin, said polymerized methyl ester of rosin having a melting point of about 212 F., a molecular weight of about 760, and an acid number of about 15.

2. A composition according to claim 1 in which said residual oil is a solvent-extract from the solvent-refining of lubricating oils.

3. A composition according to claim 1 which includes a small proportion of asphalt dissolved in the oil, suificient to increase the viscosity thereof to a selected value.

4. The composition according to claim 3 in which said residual oil is a solvent-extract from the solvent-refining of lubricating oils. 5. A petroleum lubricating composition characterized by its adhesiveness to metal surfaces, comprising about 12- 15% by weight of the dark polymerized methyl esters of rosin obtained as the residue from the vacuum distillation of the dark methyl ester of rosin, said polymerized methyl esters of rosin having a melting point of about 212 F., a molecular weight of about 760, and an acid number of about 15, 75-85% by weight of the solventextract from the solvent-refining of 150 vis. bright stock, and 5-10% by weight of the solvent-extract from the solvent-refining of neutral oils.

6. A composition according to claim 5, comprising 12% polymerized methyl esters of rosin, 81.5% bright stock extract, and 6.5% neutral oil extract, said composition having a viscosity of 485-515 SUS at 210 F.

7. A petroleum lubricating composition characterized by its adhesiveness to metal surfaces, comprising about 12-15% by weight of the dark polymerized methyl esters of rosin obtained as the residue from the vacuum distillation of the dark methyl esters of rosin, said polymerized methyl esters of rosin having a melting point of about 212 F., a molecular weight of about 760, and an acid number of about 15, 35-80% by weight of the solvent-extract from the solvent-refining of 150 vis. bright stock, and 10-50% by weight of asphalt.

8. A composition according to claim 7, comprising 12% of polymerized methyl esters of rosin, of bright stock extract, and 13% of asphalt, said composition having a viscosity of 975-1025 SUS at 210 F.

9. A composition according to claim 7, comprising 12% of polymerized methyl esters of rosin, 57% of bright stock extract, and 31% of asphalt, said composition having a viscosity of 1925-2075 SU-S at 210 F.

10. A composition according to claim 7, comprising 12% of polymerized methyl esters of rosin, 49% of bright stock extract, and 39% of asphalt, said composition having a viscosity of 2900-3100 SUS at 210 F.

11. A composition according to claim 7, comprising 12% of polymerized methyl esters of rosin, 40% of bright stock extract, and 48% of asphalt, said composition having a viscosity of 4850-5150 SUS at 210 F.

References Cited in the file of this patent UNITED STATES PATENTS 2,154,704 Schnorf Apr. 18, 1939 2,407,248 Borglin Sept. 10, 1946 2,716,085 Ayers et a1. Aug. 23, 1955 2,778,780 Romberg Jan. 22, 1957 2,785,111 Vierk et al. Mar. 12, 1957 OTHER REFERENCES Effects of Hercules Modifiers Upon Some Typical Properties of Blown Asphalts, 1943, Hercules Powder Co., pp. 12 and 16.

Petroleum Refining With Chemicals, 1956, Kalichevsky-Kobe, Elsevier Publishing Co., pp. 345-374. 

1. A PETROLEUM LUBRICATING COMPOSITION CHARACTERIZED BY ITS ADHESIVENESS TO METAL SURFACES, COMPRISING A MAJOR PROPORTION OF A CISCOUS RESIDUAL OIL OF THE CLASS CONSISTING OF RESIDUES FROM THE DISTILLATION IF LUBRICATING OILS AND SOLVENT EXTRACTS OBTAINED IN THE SOLVENT REFINING OF LUBRICATING OILS AND 1-15% BY WEIGHT OF THE DARK POLYMERIZED METHYL ESTERS OF ROSIN OBTAINED AS THE RESIDUE FROM THE VACUUM DISTILLATION OF THE DARK METHYL ESTER OF ROSIN, SAID POLYMERIZED METHYL ESTER OF ROSIN HAVING A MELTING POINT OF ABOUT 212* F., A MOLECULAR WEIGHT OF ABOUT 760, AND AN ACID NUMBER OF ABOUT
 15. 